1. Field of the Invention
The present invention relates to a paper handling apparatus, in particular, a paper handling apparatus for storing papers ejected from a copying machine or the like and stapling them by a stapler.
2. Description of Related Art
Generally, paper handling apparatuses of the type are of such arrangement that reproduced copying papers are stored onto a tray or like so that they are arranged in order thereon and, after stapling, they are transferred to a stacking station for being placed and stored therein. One such apparatus is disclosed, for example, in Japanese Patent Laid Open Publication No. 59-43765.
The apparatus is such that, after being stapled, the papers are relieved from the action of a stopper which regulates front ends of the papers and they are grasped between pinch rollers and large diameter rollers as the first mentioned rollers are caused to project into the tray, the papers being thereby discharged onto the stacking station.
With such apparatus, however, provision is required of special elements (such as rollers) for discharge of stapled papers and a mechanism for driving them which means that the apparatus is per se complicated in construction and larger in size.
In view of this problem, the present inventors made a series of studies into the possibility of developing a new upright type of paper handling apparatus in which papers are stored and arranged in order in generally vertically held condition for being stapled and processed otherwise. A paper handling apparatus of such upright type is advantageous in that less space is required for a paper working zone and, more especially, in that papers, after being stapled, can be discharged from the tray by being allowed to drop freely simply by relieving the action of a stopper positioned at the lower end of the tray. However, a mere attempt to allow free dropping of the papers may sometimes involve the trouble of positional irregularities in paper dropping if some constituent member is in contact with a paper or papers, which contact may causes a force of resistance. Especially when paper alignment means (e.g., a paddle wheel) for aligning papers in position for stapling purposes are in contact with some of the papers, such trouble is likely to occur.
Another possible difficulty is that if papers stored in an upright condition are irregularly positioned at upper ends thereof due to curling or their limpness, succeeding papers received for placement are likely to collide with the irregularly positioned papers, with the result of paper jamming. Further, in such case, the trouble is that the succeeding papers may individually break into the previously placed groups of papers, thus disturbing the order of paper placement.
Aforesaid conventional type of paper handling apparatus as, for example disclosed in said Japanese Patent Laid Open Publication No. 59-43765, employs an impeller like paddle wheel which is uni-directionally rotatable in order to align papers stored in the tray. However, such apparatus involves a problem that papers being transported by transport rollers into the tray reach the paddle wheel as they slip downward from the tray in free condition so that they may be subject to skewness depending upon the condition of their curling or their being statically electrified, which does not permit proper paper alignment.